Organic light-emitting diode (OLED) display devices, as a new type of flat-panel displays, draw more and more attention and become the next generation display devices likely to replace liquid crystal display devices, due to their characteristics such as self-illumination, high brightness, wide viewing angle, fast response, low power consumption, flexibility, etc.
Currently, a packaging method of an OLED panel is as follows: placing an OLED substrate including a plurality of display areas on a platform of a laminating machine; coating a UV glue for one or two rounds in a packaging region of a packaging coverplate to be attached to the OLED substrate (the packaging region being positioned in the peripheral area of the packaging coverplate), and coating glass frit on parts of the packaging coverplate each corresponding to a packaging area surrounding each display area; next, attaching the packaging coverplate to the OLED substrate under vacuum to form an OLED display motherboard; subsequently, irradiating the peripheral area of the packaging coverplate with a UV light under atmospheric environment, so as to cure the UV glue in the packaging region of the packaging coverplate; and then irradiating the areas coated with the glass frit with laser, so as to melt and cure the glass frit, thus completing packaging of the OLED display motherboard. After the packaging is completed, a mechanical cutter is used to cut along the packaging areas of the OLED display motherboard, so as to form a plurality of OLED panels.
The inventors found that at least the following problem exists in the prior art: the main component of the glass frit is glass powder, ceramic powder, etc., and the glass frit becomes fragile after being melt and cured by laser, therefore, when cutting the OLED motherboard, pressing and edge grinding by the mechanical cutter are likely to result in release of inner stress of the glass frit, which causes the glass frit to crack and even causes the packaging coverplate to separate from the OLED substrate, so that water and oxygen invade into an OLED device via the cracking path, which leads to black spots and bubbles in the light-emitting layer of the OLED device, finally resulting in failure of the device and shortened service life. Therefore, there is always a certain distance kept between the cutting line and the glass frit, which, however, is unfavourable for implementation of narrow bezel as the edge for grinding has limited width.